Easy choice, keep it the way it is and don't go over 50. Leave it stock and enjoy it. Next choice, a later 235 or 261 with full pressure oiling and insert bearings. Can be hopped up. For happier hiway cruising install 3.55 gears from a 1950 - 54 Powerglide model or swap in the whole rear axle. Or, you can buy the gears new. A later six, or a V8 WILL fit your present drive train if you go about it right. Both use the same (manual trans) bellhousing. This bell will fit a torque tube drive trans IF it is the right one. Usually found in 1942 - 54 1/2 ton pickups. There are 2 different trans cases but they both use all the same internal parts. Requires slight grinding of the bellhousing for clearance. The difference is the bottom bolts on the 'good' case are wider apart. It might be possible to drill the bellhousing for the other trans case but I don't know anyone who has done this. As others pointed out, the newer six is longer and requires different mounts, moving the rad forward and a few other mods. V8 not recommended with the stock drive train unless it is small and low powered like a stock 283 or 305 and you baby it. The V8 is a tight squeeze, the six a lot easier to fit. So you have some choices and you don't have to gut your car like a trout and install a whole new drive train if you don't want to. As for my personal choice - I just bought a 261 out of a 62 Canadian Pontiac for my 42 Chevy.
If you buy a 235, get one from a '55 or newer. There is a horsepower difference, and the earliest 235s from the first couple years were not all full pressure oiled if I remember correctly. I think my 1956 235 is rated for 135 hp, while the early ones were something like 115-120. If you can find one from 1960-1961 I think they may have had a few more hp.
I lean more toward leaving well enough alone and drive it. Take the two lane highways and enjoy the drive. That’s a very sharp car! Mine is still a 216. You could change rear end ratio easily with gears or complete rear end from an automatic transmission car.That would boost your top end speed. ‘51-‘54 will work.
Picking up a 235 locally tomorrow. Thank you though! Sent from my iPhone using The H.A.M.B. mobile app
No problem. I got a ton of parts to boot. Keep me in mind if you need something or just some parts or help. Another thing,, if that 216 is running decent, run it. I ran mine for 3 years and the only reasons i swapped it was for a clutch issue and the 261 was waiting on the sideline.
The biggest reason for the swap is to preserve it. It runs great and I’m going to use it til the 235 is ready. Thanks I’m sure I will be asking for advice and parts. Sent from my iPhone using The H.A.M.B. mobile app
Love that car! Are you going to start a build thread for the swap, or use this one? I may have missed it, but what transmission are you going with? Stock 3 speed and torque tube? Subscribed to this one..
Yea I’m leaving the 3 speed and torque tube. Other than that the only thing I’m changing is the motor. It’s gunna take me a little while to get the motor together. And I’m going to have to sell the Harley for the paint haha. I want to have a fresh coat of paint and clear done. Same color though keeping the fathom green. Sent from my iPhone using The H.A.M.B. mobile app
Picked up that 235 yesterday. Looks to be decent but I have to take it apart this weekend. Block casting #: 3836233 Head casting #: 3835913 SN: 0424051IT55Y I’m assuming a 55 235 from a car/truck with the PG transmission. If I’m wrong let me know. Gunna take me a while to put it together the way I want but I’ll see how it is inside this weekend when I pull it apart. Sent from my iPhone using The H.A.M.B. mobile app